"The naked truth"

If 2011 was the year of the Hollywood hook-up, with casual-sex flicks such as No Strings Attached and Friends with Benefits, 2012 seems set to be the year of the sex addict. Thursday sees the release of Shame, the critically acclaimed portrait of sex addiction starring actor Michael Fassbender. A recent Newsweek cover reported an "epidemic" of the condition, saying it was leaving a trail of destroyed marriages, careers and self-esteem in its wake. Then there is Thanks for Sharing, a new sex-addiction comedy starring Gwyneth Paltrow, due out later this year.

Sex addiction has been a media constant for several years now, thanks to serial philanderers such as Tiger Woods and Charlie Sheen. But the new breed of sex-addiction-fuelled pop culture is darker than its cynical predecessors, concerned with putting the condition on the map as a real and serious illness.

Take Shame, for example. Fassbender's Brandon might be tall and chiselled, but his life is far from enviable. Deliberately isolated, Brandon interacts only with his sleazy boss, his emotionally fragile younger sister (Carey Mulligan), and the carousel of women he brings into his bedroom. Sex comes easily to him when it is paid for or anonymous, but he falters at even the faintest flicker of intimacy. By most people's standards, Brandon has a lot of sex with a lot of different people. But is he an addict? And if so, what does that mean? ...

Proponents of the addiction theory will tell you that their model is morally neutral. Where the tabloids lambast serial cheaters for their sins, those who refer to it as an addiction seek to de-stigmatise the behaviour, explains addiction specialist Robert Mittiga, director of the GATS counselling and treatment program in Adelaide. "It's really not a moral issue. It's a serious illness," he says.

But even medical science isn't value free. Remember that as recently as the early 1970s, the American Psychiatric Association still classified homosexuality as a mental illness. Similarly, deciding who and what qualifies as a "seriously ill" sex addict and what is simply a "healthy expression of human sexuality" means drawing boundaries with highly moralistic implications. How much masturbation is too much? How many partners is too many? Is there a difference between using sex as a panacea for your frustrations and being chemically dependent on it?

Not to mention that the science of sex addiction is contested in itself. The term has been rejected for inclusion in the 2013 edition of the Diagnostic and Statistical Manual of Mental Disorders, the psychiatrists' bible. And the sex addiction screening test (SAST), one of the main tools used to diagnose sex addiction, has been criticised by high-profile sex researchers such as Dr Petra Boynton and Dr Marty Klein for being too broad and ambiguous. "All the SAST really diagnoses is high libido," says David Ley.

At times, the long list of types of sex addiction can read like an excerpt from a 19th-century catalogue of sexual deviance. Cheating, swinging and BDSM? All symptoms of sex addiction. Having sex with someone of your own sex when you think you're straight? Sex addiction. Rape and paedophilia? They're often a manifestation of severe sex addiction, too, says Robert Mittiga. Even telling sexual jokes or hugging too much can be a sign that you're a secret sex addict, according to some sources. ...